The Voluntary Aluminum Industry Partnership (VAIP) program was launched in 1995 as a joint effort between EPA and the U.S. primary aluminum industry to reduce perfluorocarbon (PFC) emissions. PFCs are potent greenhouse gases, characterized by strong infrared radiation absorption and relative inertness in the atmosphere. Primary aluminum production (PDF) (7 pp, 320K, About PDF) is a major source of global PFC emissions. The VAIP promotes the development and adoption of cost-effective PFC emissions reduction opportunities. The program is implemented through a Memorandum of Understanding (4 pp, 34K, MS Word) between EPA and primary producer companies. VAIP represents all 10 smelters operating in the U.S. and 100% of U.S. production capacity.
Aluminum is produced in much the same way it has been produced for the last century, using the Hall-Heroult process. This process involves running an electric current between a carbon anode and a cathode, through a high-temperature bath of cryolite and aluminum fluoride. Alumina (Al2O3) is fed into the bath at pre-determined intervals. When the current passes through the bath, the alumina is reduced to aluminum, which can then be removed or “tapped” from the bottom of the bath. The anodes, made of baked carbon, are immersed in the bath to complete the electric path. For more information on the primary aluminum production process, see Documents, Resources & Tools.
PFCs are emitted during “anode effects” that occur when the alumina ore content of the electrolytic process bath falls below critical levels optimal for the production of aluminum. During an anode effect, two PFCs - CF4 and C2F6 - are produced. The magnitude of PFC emissions for a given level of aluminum production depends on the frequency and duration of the anode effects. CF4 and C2F6 have global warming potentials (GWP) of 6,500 and 9,200 times as strong as CO2 and atmospheric lifetimes over 10,000 years. Thus, reducing emissions will have a significant environmental benefit for many future generations. In 2013, the U.S. primary aluminum industry’s PFC emissions were equal to 3 million metric tons of carbon dioxide.
Under VAIP, partners work toward reducing PFC emissions by minimizing the number and duration of anode effects. Technological and operational changes such as employee training, use of computer monitoring, and changes in alumina feeding techniques are used. The industry is succeeding in cost effective actions by optimizing the production process, and through operation and management practices.
Through the VAIP, PFC emissions per tonne of production were reduced by over 70% (TCE/tonne) in 2013 compared to 1990 emissions. The activities and technological innovations catalyzed by VAIP have provided both economic and environmental benefits. More detailed information on the costs of reducing PFC emissions from aluminum operations is available at High GWP Projections & Mitigation Costs.
EPA and Partner Responsibilities
- Assist partners in identifying and evaluating the factors that influence the generation of PFCs;
- Serve as a clearinghouse for technical information on successful strategies to reduce PFC emissions;
- Provide partners with recognition for their achievements in protecting the climate;
- Support the development of high-quality emissions data.
Partners agree to:
- Undertake technically feasible and cost-effective actions to reduce PFC emissions;
- Track and record PFC emission reductions through techniques developed by the partnership;
- Share with EPA and other partners non-confidential information about successful PFC emission reduction processes and technologies.
The tracking and reporting scheme implemented under the VAIP helps partners avoid contributing to the atmospheric build-up of long-lived chemicals, and enables companies to document contributions to global climate protection.